A mystery featuring antiquarian bookseller Dido Hoare - Dido is generally pleased to do business with book scout Gabriel Steen, but after he receives a disturbing call he suddenly offers her a share in a medieval illustrated manuscript. It is of unknown origin but is maybe valuable. Against her better judgement, Dido buys it and Gabriel goes off to a violent death. What is this mysterious object she now controls, and how does it link to the murder?